of course, lilacs!

Study Shows – Women Surrounded By Plants Are Happier And Live Longer
According to a research by Harvard T.H. Chan School of Public Health and Brigham Women’s Hospital, women surrounded by plants live longer. This study was conducted in the US over the course of eight years.
It was found that surrounding yourself with vegetation may increase your longevity. This is due to the increased opportunity for social engagement and physical activity, as well as less air pollution you’re exposed to.
According to the study, plants also have a positive impact on mental health. Results showed that living around greenery lowered chances of depression.